论文标题
没有封闭因果曲线的事件
No Events on Closed Causal Curves
论文作者
论文摘要
我们在半古典环境中介绍了事件，树，历史（ETH）方法的因果兼容性猜想。然后，我们证明在猜想的假设下，封闭的因果曲线上的点在QT的ETH方法的背景下是无法区分的，因此猜想意味着即使存在封闭的因果曲线，也意味着因果结构的兼容性。由于这一结果，观察者无法在封闭的因果曲线上分开任何两个点，因此没有观察到的观察。因此，我们得出的结论是，在QT的ETH方法的背景下，封闭的因果曲线没有身体意义。这表明在完整的重力理论中，时间旅行是不可能的，因此永远仍然是幻想。
We introduce the Causal Compatibility Conjecture for the Events, Trees, Histories (ETH) approach to Quantum Theory (QT) in the semi-classical setting. We then prove that under the assumptions of the conjecture, points on closed causal curves are physically indistinguishable in the context of the ETH approach to QT and thus the conjecture implies a compatibility of the causal structures even in presence of closed causal curves. As a consequence of this result there is no observation that could be made by an observer to tell any two points on a closed causal curve apart. We thus conclude that closed causal curves have no physical significance in the context of the ETH approach to QT. This is an indication that time travel will not be possible in a full quantum theory of gravity and thus forever remain a fantasy.
